HAVi is a middle ware—a software disposed between an application and an OS—and allows home-use audio/video devices (AV devices) to be controlled. The controlling targets of HAVi are the audio/video devices in accordance with IEEE 1394. The HAVi specification has disclosed an inter-operation by linking AV devices with each other as well as a Plug-and-Play function that allows users to operate AV devices just by hooking up the devices to the HAVi network.
The HAVi specification in detail is introduced in the HAVi Specification-Specification of the Home Audio Video Interoperability (HAVi) Architecture, Version 1.0 beta, available from HAVi, Inc. of San Ramon, Calif., USA. Meanwhile, various network-services in accordance with the internet protocol (IP) are available outside the homes, and an art realizing the Plug-and-Play among the devices hooked up to the internet has been already disclosed.
In order to realize a communication between the device on HAVi network and the device on the internet, the following problems should be overcome.
1. A gateway (GW) apparatus accommodating differences in physical specifications and network protocols is required. Because in these two factors, the HAVi devices following the communication protocol of HAVi specification and the devices (IP devices) on the internet following the internet protocol (IP) differ with each other.
To realize the “Plug-and-Play”, in particular, between the HAVi devices and the IP devices, the following two problems, i.e. items 2 and 3, should be overcome.
2. In order to manipulate a device plugged in the IP network (second network) from the HAVi network (first network), a user should firstly be informed that the device in the IP network is plugged in. Next, a target address such as a Uniform Resource Locator (URL) and an appropriate communication protocol should be obtained. Then the user accesses to the IP device following a process required.
3. When a user wants to manipulate the HAVi device from the IP network, the user should firstly be informed that the HAVi device is plugged in. Next, the user should obtain a target address for accessing to the HAVi device and a connecting process.
4. A stream transfer of audio and video information is assumed in the HAVi specification, and the transfer is limited within the HAVi network. A method of transferring stream information between IP devices and HAVi devices is required.
5. The HAVi specification provides the users with a graphical user interface (GUI) for improving operability of the HAVi devices. Therefore, a method of utilizing the GUI from the outside of the HAVi network is required.
6. When a GW function is prepared for overcoming the first problem discussed above, the information available in a GW apparatus may be not enough for creating a reciprocal-conversion protocol between the HAVi network and another network.